Re: [dhcwg] Review of draft-ietf-dhc-topo-conf-01

["Bernie Volz (volz)" <[e-mail]>]

Below are some comments I had sent to Tomek a while back ... I think some (or all) of these might have already been noted by others.

I also believe it is worth mentioning RFC 3257, Link Selection sub-option for the Relay Agent Information Option for DHCPv4 - as using these avoids the overloading of giaddr to be both the "location" of the client and the relay address.

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Section 10.  Mutliple subnets on the same link



Multiple is misspelled in section title.



Section 4, figure is labeled as both Figure 2 and Figure 3?



   {"prefixes":

     {"10.0.0.0/24": {"options": {"routers": ["10.0.0.1"]}

              "on-link": ["a"]}}

      "10.0.1.0/24": {"options": {"routers": ["10.0.1.1"}}

              "on-link": ["b"]}

      "10.0.2.0/24": {"options": {"routers": ["10.0.2.1"}}

              "on-link": ["f"]}

      "10.0.3.0/24": {"options": {"routers": ["10.0.3.1"}}

              "on-link": ["g"]}}





   Figure 2



                                 Figure 3



I also think the text which follows this figure should refer to figure 2, not 3.



Actually the problem is that this should be Figure 3, not 2. And the later "Figure 3" (Section 7) should be Figure 4.



(As a side issue, I wonder whether for v4 example the "prefixes" would be better as "subnet"? Also,


- Bernie

From: dhcwg [mailto:[e-mail]] On Behalf Of Qi Sun
Sent: Wednesday, March 26, 2014 7:47 AM
To: <[e-mail]>
Subject: Re: [dhcwg] Review of draft-ietf-dhc-topo-conf-01

Dear all,

I volunteered to review the document. The document is well written and easy to review. I have some comments in addition to Simon and Sheng's.

1. Sec 2, Terminology:
   an IP address with a scope of use wider than the local link.

[Qi] Is this the definition for "Link-identifying IP address"?

  provider edge router.  The provider router closest to the customer.

[Qi] Suggest:
Provider Edge router (PE router): ...

  customer premise equipment device.  Typically a router belonging to
  the customer that connects directly to the provider link.

[Qi] Suggest:
Customer Premise Equipment device (CPE device): ...

2. Sec 3, on Page 6
   In either case, the DHCP server is able to obtain an IP address that
  it knows is on-link for the link to which the DHCP client is
  connected: either the DHCPv4 client's routable IPv4 address, or the
  relay agent's IP address on the link to which the client is
   connected.

[Qi] The word "obtain" here is confusing: it seems the DHCP server obtains an IP address for its own configuration. Obviously not.

3. The 1st paragraph on Page 7
   DHCPv6 also has support for more finely grained link identification,
  using Lightweight DHCPv6 Relay Agents [RFC6221<http://tools.ietf.org/html/rfc6221>] (LDRA).  In this
  case, in addition to receiving an IPv6 address that is on-link for
  the link to which the client is connected, the DHCPv6 server also
  receives an Interface Identifier option from the relay agent that can
  be used to more precisely identify the client's location on the
   network.

[Qi] IMHO, the word "receive" here is also confusing, as "obtain" in the previous note.

4. Section 5
   Relay agent is a DHCP software that may be run on any IP node.
  Although it is typically run on a a router, it doesn't have to be
  one.  Relay agent can be run on a host connected to two links.  That
  case is presented in Figure 2.  There is router B that is connected
  to links D and E. At the same time there is also a host that is
  connected to the same links.  The relay agent software is running on
   that host.  That is uncommon, but legal configuration.

s/on a a router/on a router/
BTW, where is the host that connects to the same links with the router B in Figure 2?

Thanks for writing this.

Best Regards,
Qi